Utility companies use utility meters to regulate and monitor utility usage. Some exemplary utility meters include electrical power meters (also referred to in the industry as watt-hour meters), water meters, gas meters and the like. Early utility meters were mechanical in nature converting the flow of the particular utility resource through the utility meter into mechanical movement. The mechanical movement was used to turn a recording device which recorded the amount of resources being used. As technology improved over the years, the design of the utility meter incorporated new innovations such as increased processing capability within the utility meter, elimination of mechanical parts, better accuracy and the like.
One problem utility companies continue to deal with since the advent of the utility meter is the tampering consumer. The tampering consumer may be an individual who desires to alter the monitoring capabilities of the utility meter. By altering the monitoring capabilities of the utility meter, the tampering consumer may receive some or all of the utility resources at a significantly discounted rate. This presents a problem not only with the theft of the utility resource but also with the potential safety hazard that may be caused by the tampering consumer. The potential safety hazard may in turn affect other utility consumers connected to the power grid.
Previous utility meters may have had some means of detecting tampering with the utility meter. Commonly, a sensor may have been configured in previous utility meters to monitor the cover of the utility meter. Thus, when a tampering consumer opened the utility meter cover, an alarm condition may have been generated by circuitry within the utility meter. The alarm condition may then be reported in various ways to the utility company. Depending on the number of alarms, the frequency of the alarms and the like, the utility company may take any remedial action it deemed necessary in order to confirm and remedy the tampered condition.
Other means have been used in previous utility meters to detect tampering. Another example of previous ways to detect tampering with a utility meter was to employ a movable and conductive metal ball contained within a metal housing. The metal ball was positioned to move from a resting position to an alarm position if the utility meter was physically moved. If the utility meter moved in a certain direction, the ball would roll from the resting position to an alarm position which may be on the opposite side of the metal housing. When the ball transitioned from the resting position to the alarm position, the metal housing became conductive and the utility meter then detected the conductive change. After the utility meter detected the conductive change, the utility meter raised an alarm condition alerting the utility company of the potential tampered condition.
The previous method of detecting tampering using a mechanically moving conductive ball may not detect to certain types of movement of the utility meter. The utility meter may be moved in such a way as not to activate the mechanically moving conductive ball tampering detection circuitry. In addition, this type of detection circuitry may be costly to deploy within the utility meter. In some cases, this type of detection circuitry may not be mounted using surface mount technology and may have to be hand soldered within the utility meter. To more effectively detect possible utility meter tampering at a much lower cost, the present invention utilizes the piezoelectric properties of a ceramic capacitor to detect movement of the meter. Circuitry associated with the present invention located within the utility meter monitors and detects when the ceramic capacitor experiences any mechanical strain, and provides a way for the utility meter to signal the utility company of possible meter tampering.